Abstract:During the long-term operation of cable accessories,the interface silicone grease is in direct contact with the insulation silicone rubber,so that it is gradually absorbed by the silicone rubber,resulting in the performance degradation of silicone rubber,and even the interface problems of cable accessories. Based on the weight increasing test of silicone rubber absorbing silicone grease for accessory insulation,the diffusion rules of silicone grease/silicone oil in silicone rubber at different temperatures are studied and the corresponding diffusion parameters are obtained. The influence of silicone grease on the electrical properties of silicone rubber,such as volume resistivity,relative dielectric constant,dielectric loss angle tangent value and power frequency breakdown field strength,is investigated. The results show that the diffusion law of silicone grease/silicone oil in silicone rubber follows the Langmuir diffusion model at different temperatures. The absorption capacity of silicone rubber to silicone grease/silicone oil increases with the increase of temperature,and the desorption process of silicone oil molecules in silicone rubber is stronger. With the increase of the absorption amount of silicone rubber to silicone grease,the volume resistivity of silicone rubber decreases gradually,the relative dielectric constant and the tangent value of the dielectric loss angle increase gradually,but the breakdown field strength of its power frequency first increases and then decreases.